1. Field of the Invention
The present invention relates generally to flooring for play systems, and more particularly to a webbed floor for a play system in which the webbing is pre-tensioned, weaved, and attached to a frame by one of several attachment techniques.
2. Description of the Prior Art
Play systems for children are well-known in the art and have evolved into a major industry in the United States. A typical play system, such as shown in FIG. 1, is constructed of a tubular metal frame 2 and may include, for example, one or more enclosed or unenclosed slides 4, platforms 6 at different heights, enclosed or unenclosed passageways 8, a ball bin 10 (balls not shown), monkey bars, trolleys, and other recreational elements suitable for use by children.
The flooring for a play system must generally meet two criteria; it must be resilient so that children may play without injuring themselves, and it must be able to endure prolonged abuse by thousands of children. The simplest type of flooring for a play system is constructed of vinyl or other durable material that is attached to the frame, generally by forming a loop at the end of the flooring and sliding the frame members through the material. These types of floors suffer from several shortcomings. First, the materials used for the floor tend to stretch and sag over time, thereby requiring replacement of the flooring and resulting in loss of enjoyment of the play system by the children. Second, since the vinyl or other material is opaque, parents who are concerned about their children's safety on the upper platforms of the play system may lose sight of their children.
In an attempt to overcome these short comings, layered web floors, such as shown in FIG. 2, were developed. This type of floor consists of straps of webbing, 14 and 16, made of nylon or other material, which are oriented perpendicular to each other. At their ends, the web straps are wrapped around the frame members 12 to form a loop and are sewn to themselves. In this type of webbed flooring, all of the straps that are oriented in one direction. e.g., straps 14, are located either above or below all of the straps oriented in the other direction, e.g. straps 16. Where the straps 14 and 16 pass over each other, they are sewed together.
This type of webbed flooring also suffers from several shortcomings. First, when a child is standing on a single web strap on the lower layer of straps, the stitching that attaches the strap to the upper layer of strap bears much of the weight of the child. Consequentially, the stitching tends to tear over time, resulting in separation of the layers of the floor and requiring replacement of the floor. Second, this type of floor also tends to stretch over time, thereby requiring relatively frequent replacement.
In this type of floor, an alternative method of attaching the webs to the frame may he used. Each web may include a loop at each end formed by sewing the web to itself. The webbing is made to alternate between straps that are shorter, having a length extending approximately the length between opposed frame members, and longer length webs, sized so that the loops at the ends of the longer webs pass around the frame members and align with the loops at the ends of the shorter straps. A relatively rigid rod is then passed through the aligned loops of the shorter and longer webs. The webs passing around the frame secure the floor to the frame. These types of floors are difficult to assemble, and tend to sag due to the difficulty in tensioning the floor as a result of the difficult assembly procedure.
In order to reduce the tendency of play system floors to sag, the floor may be tensioned. One known method of tensioning the floor is to attach springs to the floor. This type of system is used, for example, in trampoline floors. Use of this type of tensioning system is not desirable because the springs are expensive and remain exposed, thereby endangering children on the play system.
In another type of tensioning system, as shown in FIGS. 3 and 4, one loop of a tensioning harness 18 is attached to a rod 20 running around the perimeter of the floor through loops in the flooring material. The other loop of the harness is attached to the frame around the base of the floor. In either of these methods, i.e., using springs or a tensioning harness, the tensioning device becomes a permanent component of the floor, thereby making such floors more expensive.
One object of the present invention is to provide a play system floor that is durable and that is pre-tensioned so as to be resistant to sagging. Another object of the present invention is to provide a plan system floor in which the tensioning device does not become a permanent part of the floor, or which utilizes inexpensive components so as to reduce the cost of such a floor.